Postby Guest » Fri Jun 11, 2004 2:31 am
Foils are vastly superior to Leading Edge pump up kites ( water wings). I've summarized the reasons for the superiority of Foil Kites:
1: Lift to drag ration (L/D)
- The highest L/D ratio is not always optimal. A high L/D ratio is critical in large kites because they move slowly. Large kites output steady power but generally lose out in ability to turn suddenly and generate sudden upward pull.
- Because large LE kites have a HUGE "D" coefficient compared to Foils, they are unable to generate the sudden upward power spikes.
- For this reason, large LE kites can pull steadily enough, but will ALWAYS lack the jumping ability of a large quality 2004 Foil. E.g. Flysurfer PS2- 21 or 26 m kites
-Small kites move rapidly and therefore have large power spikes. These kites are INTENTIONALLY designed to move slower by ram and inflatable manufacturers. The lack or presence of a leading edge/ram cells is really irrelevant in the small sizes since SLOWNESS is a virtue in these sizes. The things to look for in these sizes are luff curve, chord, aspect ration for aerodynamic handling.
2: Inertia
- Because large LE kites have a much larger mass of air in them (filling the bladders) their inertia is enormous. It is very difficult moving this mass of air across the sky to generate sudden power spikes and therefore lift. The inertia and slow turning makes a lot of modern moves (eg kiteloops) incredibly difficult, if not impossible using a 30m Nash Kite. Large LE kites like the Nash 30 contain OVER 11kg of air in their bladders!!!!.
3: Rigidity
- Small ram airs are better than small LE kites because they have a semi-rigid structure produced by bridles and internal cell configuration. This improves consistency, stability of turning, and precision in handling. Kite makers like Naish, Cabrinah ( see new Contra kite ) North ( 5th element) , and Slingshot are actually moving to make their kites MORE rigid by joining the struts firmly to the leading edge using bridles!!!!!!. See 5th element, and adaptations of on this forum.
-Rigidity also facilitates turning. Bar pressure TWISTS the WHOLE kite, speeding up turns. Lack of internal rigidity means that LE kites can't turn as aerodynamically as Ram Air kites which use a proven bridle structure for support..
4: Wing tips
- the tips of the inflatable kite act as rudders, slowing down the kite, with less control on turns (and therefore smaller more controlled power spikes)
5: Foil shape
- Ram Airs have a consistent foil shape because they are semi rigid by the use of bridles. LE kites deform and change their foil shape which causes an inconsistent aerodynamic profile......jelly fishing etc.
6: Luff curve
- If you want a flat luff curve, choose an X3 or similar
- If you want a deep luff curve, choose a Rhino2 or similar
- If you want in-between, choose a Slingshot or similar
- One ram air kite can now do all of the above in one kite by the use of different settings, See Psycho 2, or Voodoo kites that allow for different kite shape settings depending on you riding style and wind conditions.
7: Relaunch
- This is a BIG Issue. Beginners find relaunching inflatable kites very hard and it takes MANY sessions to learn this skill.
Rams Air can reverse launch,
Rams Airs can launch directly downwind in the water,
Ram Air kites can Solo or assisted launch at the side of the window like a LE kite with no drag
Relaunching inflatables is way too hard and was a design lemon patented by 2 ignorant French men 15 years ago ……there have been no new advances in LE designs since then……
If you are an experienced kiteboard rider ask yourself when you last droped your kite in the water. Probable you have dropped your kite in the last 10 sessions on the water. So why are you flying and inflatable kite????, as stated above Inflatable kites are an inherent design flaw? Really have the French ever come up with anything good in designs?,???
8: Safety
- Ram Airs are safer than LE kites because
-- LE Side launches are bloody SCARY for a beginner
-- Pump UP kites deform, twist, explode in the middle of the power zone etc when they are downwind of obstacles, in rotors, and in VERY gusty conditions. This is VERY dangerous. Some of the most frightening kitemares I've witnessed have involved LE kite users walking along beaches in cross-offshore conditions - their kites have been virtually uncontrollable and have endangered both the rider and other beach users.
-- Wind dropouts and gear failure
--- You will invariably experience a few catastrophic gear failures (LE Kite exploding) and COMPLETE wind dropouts every year. If you are a fair way offshore, you cannot use the inflatables as a "sail" to sail back in as it has exploded bladders. Alternatively you can use the Ram Air structure to support your weight, even with a punctured cell or two.
--- All LE kites become hopelessly waterlogged Once the bladder explodes- unlaunchable and certainly unable to support your body weight.
-- Surf conditions
---While it is always a gamble if your kite gets caught by a wave, at least you've got a chance if its a Foil to launch quickly. If it is a LE kite, it's all over.
9 Pre-inflating -----Beats Pumping ANY DAY of the week!!!.
- Rams are easy to pre-inflate
- With pre-inflation, ram users find it very easy to drift launch. This skill is often required eg Promontory/headland launches.
10 Resale
- Contrary to the propaganda of LE lovers, ram airs have 3 x the lifespan of the inflatos . The major determinant of a kite lifespan is marketing, now all LE kites are not worth much 2nd hand due to BEST and new LE marketing cheap products. There is no such player in Foils and you will get TOP dollar for you 2nd hand Ram Air kite that will last at least 200 hours flying time, see FS warantee
11 Repairs
- Ram air repairs are generally Cheeeeeeeeeeep. For example, most Foilr kites require little repair. Repairing a Bladder is like having sex with you Grandmother.....something you dread, something you dont want to do.....
Something you don’t want to tell your friends about….
12 Competition
Ram lovers have proved their claims in competitions. See Tobys Light Wind Weapon VId
Ignore the LE and PMU propaganda. Ignore the lies. Ram airs are aerodynamically superior to LE Kites and nothing can change this